Valve.



No. 760,488. PATENTED MAY 24, 1904. H. G. ROOT.

VALVE.

APPLICATION FILED MAR. 19, 1904. NO MODEL.

' 5] box NH/ mow WW" I 94 By Harry 0.1mm

.THE NORRIS PETERS co. wasmuamu, u c

fatented May 24, 1904.

PATENT OFFICE.

HARRY-C. ROOT, GI CHARLESTON, ILLINOIS.

.vALVE.

SPECIFICATION forming part of Letters Patent No. 760,488, dated May 24,1904.

Application mantra 19, 1904.

To all whom it may concern:

Be it known that I, HARRY O. Roo'r, a citizen of the United States,residing at Charleston, in the county of Coles and State of Illinois,have invented certain new and useful Improvements in Valves, of whichthe following is a specification.

The object of myinvention is to produce apressure reducing andcontrolling valve which shall in operation be doubly balanced, the ar*rangement being such that the pressure-controlling means shall benormally out of action when the desired pressure is maintained.

The accompanying drawing, which is a cen-, tral vertical section, showsthe parts in the positions' occupied when the parts are in normaloperating position.

In the drawing, 10 indicates a suitable casing, having a cylinder 11formed in one end and a secondary-pressure chamber 12 formed ,in theother end. Leading into the upper end of cylinder 11 is a mainsupply-port 13, with which communicates the main supply-pipe 14. Leadingfrom cylinder 11 at a point slightly below the port 13 is a port 15,which through a by-pass 16 leads into chamber 12. Leading from chamber12 is the main eduction-pipe 17 The upper end of casing 10 is closedby ahead 18, which is provided with an adjustable spring-abutment 19,against which one endof the pressure-controlling spring 20 abuts. Thelower end of casing 10 is closed by a head 21, provided with a suitablepacking-gland, through which the piston-rod 22 extends. Below head 21 isarranged a-cylinder 23, the lower end of which is closed, and leadinginto this end is a port 24, which also communicates with the mainsupply-pipe 14. The piston-rod 22 carries at its upper end a piston 25,which fits cylinder 11 and is adapted to be brought opposite port 15 toclose the same. Secured to the lower end of piston rod 22 is a piston26, which at all times lies 1 above port 24.

Serial No. 198,898. (Nn'modoh) to the square inch to balance the same,and

as pressure is admitted through pipes 14 it will pass simultaneouslythrough the ports 13 and 24 into the upper end of cylinder 11 and thelower end of cylinder 23, whereupon structure 22 25 26 becomes balanced.Thefiuid also passes through port 15 and by-pass16 into chamber 12 andfrom thence out the eduction-pipe 17. As soon as there is any pressurein chamber- 12 this pressure acts upon the lower side of piston-head 25,thus raising the piston structure and bringing into action the spring20. As soon as the .pressure within chamber 12 becomes equal to thestrength of the spring the port 15 will have been closed a sufiicientamount to preventaccumulation of more than the desired amount ofpressure in the chamber 12. The valve structure is therefore at alltimes substantially balanced, the initial pressure through the pipe 14acting equally upon the top and bottom of the piston structure,whilethespring 20 and the weight of the piston structure is balanced by thereduced pressure in chamber 12. As a consequence the spring 20 does notcontrol the reduced pressure by continuous opposition against theinitial pressure, but remains but little uncompressed during normaloperation, becoming materially compressed only'when the pressuremomentarily increases in the chamber12 beyond the desired maximum, sothat there is not the continuous possibility of the breaking of thespring, asis the case in reducing-valvesof the spring type now commonlyin use. It will also be noticed that the port 15 is always in directcommunication with the induction-port 13.

It will be readily understood that my device may be used in any placewhere a reduced pressure is desired-as, for instance, in steam plants,natural-gas mains, in water-mains, as

a pressure-controlling valve for airbrakes, mines, and other air plants,and many other places too numerous to mention.

If at any time the initial pressure falls'be; low the maximum desired,the entire initial pressure will pass through the valve unhindered, forthe reason that under such circumstances the piston drops to its lowestpoint and the spring plays no part at all in the op (nation, and it alsowill be noticed that any sudden rise in the initial pressure will notthrow any extra stress on the spring nor affect. the secondary pressurein the least.

I claim as my invention 1. Ina pressure-controlling valve, the combination,- with a suitable casing'having a pair of initial-pressurcchambers and a secondarypressure chamber formed therein, inductionportsleading into each of the initial-pressure chambers and a by-pass leadingfrom one of said initial-pressure chambers to the secondary pressurechamber, of a valve structure arranged in said casing and adapted tocontrol the eflf'ective area of the by-pass, said valve structure beingso arranged as to be'engaged in opposite directions by the initialpressure and by thesecondary pressure in the secondarywpressure chamberin opposition to the di-' rection of pressure upon the valve structurein one of the initial-pressure chambers, andasecondarypressure-determining device arranged to engage the valve structure in oppositionto the pressure in the secondary-pres-' sure chamber. 2. Apressure-controlling valve structure consisting of, a casing having apair of initialpressure chambers, a secondary-pressure chamber, aninduction-port leading into each of the initial-pressure chambers, aby-pass leading from one of said initial-pressure chambers to thesecondary-pressure chambers, and an eduction-pipe leading from thesecondarypressure chamber, of a piston structure having a pair of headsone mounted in each initial-pressure chamber and adapted to be engagedby the initial pressure in opposite directions, one of said pistonsbeing adapted to control the effective area of the by-pass and one'ofsaid pistons having one end arranged-in the secondary-pressure chamber,and a secondary-pressure-controlling spring arranged to engage thepiston structure in opposition to the pressure exertediuponthe pistonstructure from the secondary-pressure chamber.

3. A pressure-controlling valve structure consisting of, a casing havinga pair of initialpressure chambers, a secondary pressure chamber, aninduction-port leading into each of the initial-pressure chambers, aby-pass leadv ing from one of said initial-pressure chambers to thesecondary-pressure chambers, and an eduction-pipe leading from thesecondarypressure chamber, of a piston structure having a pair of headsone mounted in each initial-pressure chamber and adapted to be engagedby the initial pressure in opposite directions, one of said pistonsbeing adapted to control the eflective area of the by-pass and one ofsaid pistons having one end arranged in the secondary: pressure chamber,a secondary-pressure-controlling-spring arranged to engage the pistonstructure in oppositionto the pressure exerted upon the piston structurefromthesecondarypressure chamber, and means for adjusting the effectivepressure of said spring.

4. A pressure-reducing valve consisting of,

a pair of initial-pressure cylinders each having an induction-port, a'piston structure consisting of a pair of separated heads one arrangedin'each of said initial-pressure cylinders, a secondary-pressure chamberarranged adjacent and communicating with one of said piston-heads inopposition to its initial-pressure cylinder and having a bypassleading apair of initial-pressure cylinders each hav-- ing an induction-port, apiston structure consisting of a pair of separated heads one a1" rangedin each of said initial-pressure cylinders, a secondary-pressure chamberarranged adjacent andcommunicating with one of said piston-heads inopposition to its initial-pressure cylinder and having a bypass-leadingaround said piston and communicating with the opposedinitial-pressure'cylinder, said pistons being arranged to control theeffective area of the by-pass, and a spring arranged in saidlast-mentioned initial-pressure cylinder to engage the piston structure.in opposition to the pressure exerted thereon fromthesecondary-pressure chamber. I

6. A pressure-reducing valve consisting of, a pair of initial-pressurecylinders each having an induction-port, a piston structure consistingof a pair of separated heads zone arranged in each of saidinitial-pressure'cylinders, a secondary-pressure chamber arrangedadjacent and communicating with one of said piston-heads in oppositiontoits initial-pressure cylinder and havinga by-pass leading around saidpiston and communicating with the opposed hiitial-pressurecylinder, saidpistons being arranged to control theeffectivearea of the by-pass, aspring arranged in said last-mentioned initial-pressure cylinder toengage the piston'structure in opposition to the.

pressure exerted thereon from the secondarypressure chamber, and meansfor, adjusting the effective force of said spring.

In witness whereof I have hereunto set my hand and seal, at Charleston,Illinois, this 15th day of March, A. D. 1904.

HARRY (J. ROOT. [1,. s.] Witnesses:

J. B. Rosennnuon, GEo. H. DAVIS.

